This invention relates to on-demand power reduction with a storage subsystem of a data site. More specifically, the invention relates to power management of storage elements within the data center that minimizes loss of performance with respect to data access.
Cloud computing is a model of service delivery for enabling convenient, on-demand network access to a shared pool of configurable computer resources, e.g. networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services, that can be rapidly provisioned and released with minimal management effort or interaction with a provider of service. One of the characteristics of cloud computing infrastructure is that applications can be launched from a plurality of locations with each location referred to herein as a data site. Executing applications and processing data responsive to the application execution consumes power, which in some circumstances needs to be regulated. Power reduction may occur on a periodic or temporary basis. A periodic basis pertains to power reduction coming at a set frequency, and a temporary basis pertains to a reduction that is not on a set frequency. Power reduction of a data site may be required for circumstances external to power delivery. For example, power reduction may be necessary due to failure of an external cooling mechanism. In one embodiment, periodic power reductions can be accounted for with greater precision than temporary power reductions. One common element with respect to power consumption is the need to maintain a level of performance that allows for uninterrupted data processing and access to computer resources.
For each category of power reduction, there is a need to balance power allocation and performance of applications and associated data processing. In one embodiment, the aspect of balancing may mean that the power reduction target is reached, while minimizing performance loss on data access to the storage system(s). Accordingly, balancing power in a computing environment is challenging.